Evaluation of Shear Strength of a Miniature Lead-free Single Solder Ball Joint

초소형 무연 단일 솔더볼 연결부의 전단강도 평가

  • Joo, Se-Min (Graduate School of NID Fusion Technology, Seoul National University of Science and Technology) ;
  • Kim, Ho-Kyung (Department of Automotive Engineering, Seoul National University of Science and Technology)
  • 주세민 (서울과학기술대학교 NID 대학원) ;
  • 김호경 (서울과학기술대학교 자동차공학과)
  • Received : 2010.06.28
  • Accepted : 2010.11.19
  • Published : 2010.12.31

Abstract

A miniature single solder ball joint is designed to mimic the actual solder joints used in the micro-electric industries. Shear tests were conducted to evaluate the mechanical behavior of miniature single solder joints at intermediate strain rates from $0.019\;s^{-1}$ to $2.16\;s^{-1}$ at room temperature. The shear fracture strength of the present solder ball joints generally increased with increasing shear strain rate, ranging from 32 to 51MPa. This behavior is affected by the sensitivity of bulk solder strength to strain rate. Shear fracture mode changed from brittle to partial ductile (failure inside the bulk solder) with an increase of shear speed. The unloading shear fracture toughness is generally consistent with the measure of the amount of bulk solder on the fractured surface.

Keywords

References

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